"I’ve been online and looked at all the theories," Moffat told us, "and there’s one clue that everyone’s missed. It’s something that Sherlock did that was very out of character, but which nobody has picked up on."

So it’s time to revisit – yet again – any strangely un-Sherlock behaviour from The Reichenbach Fall, and our users’ theories can be broadly split into three areas: the rooftop showdown, Molly...and hot beverages…

The rooftop

“Was the clue perhaps that Sherlock didn't search Moriarty's body for the code to stop the snipers?” asks sand_763. “We know he doesn't have a problem with a dead body, yet he left it alone and even covered up his nose and mouth... That was also a little weird...”

“I have to imagine there's something more going on with the ‘moment of privacy’ Sherlock requests from Moriarty as he's standing on the ledge,” says LW2. “It struck me immediately as a very un-Sherlock thing to do…”

And aamadis is among those who think they have the answer: “Sherlock planned to fake kill himself when Moriarty was still alive, but he couldn't have Jim looking over the edge after he jumped and seeing him land in a rubbish truck when he's trying to fool him. So he asks Jim to step back and give him some privacy so he can get a head start. Of course after Moriarty kills himself there's no need for that any more.”

Molly

Sherlock’s treatment of his pathologist admirer, Molly Hooper, is seen as being of particular significance by many.

“Sherlock left Molly out of his list of friends.. on purpose?” wonders sand_763. “To distract Moriarty? To take all attention away from the one person who could save him?”

“He was nice to Molly! I think that's it,” says Ofelia.

"Sherlock did an… out of character thing in this episode. He was very honest with Molly in the lab about needing her help. (Nowhere to stash a trolley containing a dead person on that rooftop)," says L.